1. Field of Invention
The present invention generally relates to radio broadcasting methods and specifically to radio broadcasting methods that involve both local and wide area radio broadcasting.
2. Prior Art US Patent
Radio receivers receive broadcast radio signals and convert them into audio signals to be heard by listeners. These broadcast radio signals are usually from broadcast radio stations that transmit radio signals to a wide area of population. This system has served well until now as broadcast radio stations distribute desired content over the air based on demographics of population.
But with advent of internet and mobile devices, listeners are seeking highly customized content tailored to individual tastes and expect such content to be available on demand. In particular listeners desire to hear personalized audio content while in an automobile. Although personalized audio content can be heard using headphones associated with personal audio players, it is impractical and often not recommended for use while driving due to safety concerns.
Hence there is a need for a personalized audio system that can leverage a high fidelity audio system of an automobile. Currently there are several solutions addressing this need.
One solution is to connect a personalized audio player into a cassette player of the automobile using a cassette adapter. But this solution does not address all automobiles as most new automobiles do not have a cassette player.
Another solution is to use a local area radio transmitter along with a personal audio player. Local area radio transmitters transmit radio waves to reach a small local distance. Such local area radio transmitters are available in the market and are marketed as Frequency Modulation (FM) transmitters.
Although this can be a good solution to solve the need for personalized audio content in an automobile, it suffers from various problems. Local area radio transmitters have to transmit at the same frequency as wide area radio transmitters. The signal strength of a wide area radio transmitter is usually far greater than the signal strength of a local area radio transmitter. Hence if a user transmits using a local area radio transmitter into a channel that also has signals from a wide area radio transmitter, there will be a collision between the two signals. This will give rise to intermittent noise or even complete suppression of local area radio transmitter signals. Hence a user may be prompted to change channels and scan for another channel that may have less collision.
But since most broadcast radio channels use licensed spectrum, it is very rare to find a radio channel that is unused across cities. Hence if a user is traveling in an automobile across cities, the chance that a particular channel will remain collision free for prolonged periods of time is slim.
Hence there is a need for a system that enables personalized audio content delivery in an automobile that does not suffer from the above mentioned problems and provides a clear collision free personalized audio listening experience.
Currently there are no known prior art methods that offer a solution to this problem.
Following paragraphs in current section describe relevant prior arts in this field.
Prior art U.S. Pat. No. 7,110,720 describes a system to play on demand audio content from internet using a device capable of receiving internet audio content and transmitting the audio content using local FM radio transmitting. Although this prior art addresses part of the need to provide on demand audio content, it does not address the problems that local FM radio transmitting will encounter as described above. Hence this prior art does not address the need for a clear collision free personalized audio listening experience in an automobile.
Prior art U.S. Pat. No. 6,928,308 describes a accessory device that works with a mobile phone to enable audio content in the mobile phone to be heard using a local area FM transmitter. This prior art enables the local area FM transmitter to automatically detect which channel a FM receiver is tuned to, so that the FM transmitter can automatically tune to the same channel, thereby reducing an extra step for a user to setup the appropriate channel in the local area FM transmitter. But this does not address the need for a clear collision free personalized audio listening experience in an automobile. The methods suggested by this prior art will also suffer from the collision problems as described above.
There are FM transmitters in the market that will automatically scan for the best possible channel to use for transmission, but such scans may yield poor results in a densely populated urban area where most channels are taken. Also, if an automobile is crossing over broadcast areas, a seemingly clear channel in one area may be occupied in a neighboring area and hence prompting for another channel scan and corresponding channel change in the receiver. Hence this solution does not provide an uninterrupted service and does not address the need for a clear collision free personalized audio listening experience in an automobile.
As can be seen from above, all known prior arts suffer from some limitations in offering a solution to address the need for a clear collision free personalized audio listening experience in an automobile.
3. Objects and Advantages
Accordingly, several objects and advantages of the present invention are:                a) to provide clear collision free personalized audio listening experience in an automobile;        b) to provide a method that enables radio channel owners to maintain advertisement revenue while providing for personalized audio listening experience; and        c) to provide for additional revenue opportunities to radio channel owners while providing for a personalized audio listening experience.        